- Collins Dictionary Online
- Collins Reverso: English Synonyms dictionary with synonyms, examples and antonyms
- Dictionary.com: monolingual (English - English) dictionary
- Encyclopedia.com
- Encyclopaedia Britannica
- Library Spot: reference link list
- Little Explorers: picture Dictionary with Links
- Merriam Webster: dictionary and thesaurus
- Merriam Webster - Online Picture Dictionary
- Picture dictionary for Kids
- Synonymy: synonyms sorted by categories
- Safe Search for Kids:the Google kids search engine
- The Free Dictionary: Dictionary, encyclopedia, and thesaurus
- Thesaurus.com: synonyms, antonyms, related words, and more
- Vocabulary.com: dictionary and other vocabulary activities
- Word Hippo: synonyms, antonyms, meanings, word forms, rhyming words, translation and pronunciation tools.
- Word Reference: multilingual dictionary
- Howjsay: A free online talking dictionary of English pronunciation